A retrovirus by any other name…
When we think of viruses we often think of how they act and manifest nowadays, even going so far as to associate them with hospitals. But viruses have been living on our planet well before we were even close to developing great ape forefathers on its surface.
According to a team of researchers from the United States, retroviruses were around over 30 million years ago, and they wreaked havoc on the mammalian life back then as well. I guess that’s what made those viruses truly retro.
ERV-Fc, as the 30 million year old virus was dubbed was a retrovirus – the same as HIV or T-cell leukemia. They infected a very wide range of hosts, regardless of species; primates, carnivores, rodents, they were all potential hosts, with very few animals free of risk.
Very interestingly, the virus had a huge distribution, nearly worldwide. Evidence was found that ERV-Fc managed to travel to all of the continents except for Australia and Antarctica, and that it jumped from one species to another, mutating, becoming more devastating, at least twenty times.
According to Welkin Johnson, researcher with the study and professor at the Boston College in the United States,
Viruses have been with us for billions of years, and exist everywhere that life is found. They therefore have a significant impact on the ecology and evolution of all organisms, from bacteria to humans. Unfortunately, viruses do not leave fossils behind, meaning we know very little about how they originate and evolve.
Over the course of millions of years, however, viral genetic sequences accumulate in the DNA genomes of living organisms, including humans, and can serve as molecular ‘fossils’ for exploring the natural history of viruses and their hosts.
By using these so-called fossils, the researchers looked at the places and time periods where these pathogens could be found in the ancient world, at the way in which they managed to adapt to mammal hosts, and even at which species they managed to infect.
For every one of the genomes that contained enough of the virus’ sequence, the team rebuilt the sequence of proteins that represented the virus and found out the ancestors of which animal got sick and which didn’t – basically, the ancestors of what today animals could catch ERV-Fc.
Seeing as virus was in fact a retrovirus, like HIV, researchers are looking forward to examine it as best they can – to find out how it came along, how it finally disappeared, and to see if they can use anything they learned from the long-gone ERV-Fc to easier crack the HIV epidemic.
Image source: Wikimedia
